Monday, May 29, 2017

Graph : Shortest path

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.Scanner;
import java.util.Stack;
import java.util.StringTokenizer;

public class Solution {
 static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;
 
        public FastReader()
        {
            br = new BufferedReader(new
                     InputStreamReader(System.in));
        }
 
        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException  e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
 
        int nextInt()
        {
            return Integer.parseInt(next());
        }
 
        long nextLong()
        {
            return Long.parseLong(next());
        }
 
        double nextDouble()
        {
            return Double.parseDouble(next());
        }
 
        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
 
  public static void main(String[] args) {
   FastReader in=new FastReader();
   int t1=in.nextInt();
        for(int gj=0;gj<t1;gj++){
        int n=in.nextInt();
        int m=in.nextInt();
        long w[][]=new long [n+1][n+1];
        for (long[] row: w)
            Arrays.fill(row, 1000000l);
         for(int i=0;i<m;i++){
             int x=in.nextInt(),y=in.nextInt();
             long cmp=in.nextLong();
             if(w[x][y]>cmp){
             w[x][y]=cmp; w[y][x]=cmp;
             }}
         Stack <Integer> t=new Stack<Integer>();
          int src=in.nextInt();
        for(int i=1;i<=n;i++){
         if(i!=src){t.push(i);}}
        Stack <Integer> p=new Stack<Integer>();
        p.push(src);
        w[src][src]=0;
         while(!t.isEmpty()){int min=989997979,loc=-1;
        for(int i=0;i<t.size();i++){
         w[src][t.elementAt(i)]=Math.min(w[src][t.elementAt(i)],w[src][p.peek()]+w[p.peek()][t.elementAt(i)]);
            if(w[src][t.elementAt(i)]<=min){
             min=(int) w[src][t.elementAt(i)];loc=i;}
        }
        p.push(t.elementAt(loc));t.removeElementAt(loc);}
         for(int i=1;i<=n;i++){
          if(i!=src && w[src][i]!=1000000l){System.out.print(w[src][i]+" ");}
          else if(i!=src){System.out.print("-1"+" ");}
         }System.out.println();
         }
  }}

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